title: Optimal production of polyhydroxyalkanoates (PHA) in activated sludge fed by volatile fatty acids (VFAs) generated from alkaline excess sludge fermentation.
abstract: To reduce the production cost of polyhydroxyalkanoates (PHA) and disposal amount of excess sludge simultaneously, the feasibility of using fermentative volatile fatty acids (VFAs) as carbon sources to synthesize PHA by activated sludge was examined. At pH 11.0, 60 degrees C and fermentative time of 7d, the VFAs yield was 258.65 mgTOC/gVSS. To restrain cell growth during PHA production, the released phosphorus and residual ammonium in the fermentative VFAs was recovered by the formation of struvite precipitation. Acetic acid was the predominant composition of the fermentative VFAs. PHA accumulation in excess sludge occurred feeding by fermentative VFAs with aerobic dynamic feeding process. The maximum PHA content accounted for 56.5% of the dry cell. It can be concluded from this study that the VFAs generated from excess sludge fermentation were a suitable carbon source for PHA production by activated sludge.
authors.affiliation: School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin, China. cmm_hit@126.com
authors.forename: Cai
authors.initials: C
authors.lastname: Mengmeng
authors.forename: Chua
authors.initials: C
authors.lastname: Hong
authors.forename: Zhao
authors.initials: Z
authors.lastname: Qingliang
authors.forename: Sin Ngai
authors.initials: SN
authors.lastname: Shirley
authors.forename: Ren
authors.initials: R
authors.lastname: Jie
mesh_terms: D000468:Alkalies / Q000737:chemistry; D001421:Bacteria, Anaerobic / Q000378:metabolism*; D005232:Fatty Acids, Volatile / Q000378:metabolism*; D005240:Feasibility Studies; D005285:Fermentation; D007220:Industrial Waste / Q000517:prevention & control*; D054813:Polyhydroxyalkanoates / Q000378:metabolism*; D011786:Quality Control; D012722:Sewage / Q000382:microbiology*
chemical_list: D000468:Alkalies; D005232:Fatty Acids, Volatile; D007220:Industrial Waste; D054813:Polyhydroxyalkanoates; D012722:Sewage